A rapid method was developed for the determination of 22 pesticides in rice wine. The procedure involved an extraction with acetonitrile and a cleanup step using dispersive solid-phase extraction (d-SPE), and primary-...A rapid method was developed for the determination of 22 pesticides in rice wine. The procedure involved an extraction with acetonitrile and a cleanup step using dispersive solid-phase extraction (d-SPE), and primary-secondary amine (PSA) and octadecylsilane (ODS) were used as sorbents. D-SPE had some advantages over some traditional prepara- tions, especially in time and cost. Both the extraction and cleanup only cost about 15 min per a sample. Then the GC-MS was used for quantitative and qualitative analysis. Matrix-matched standards solution and analyte protectant were compared to decrease the matrix effect, and the former showed a better efficacy. Acceptable linearity was achieved in the range of 0.05 - 0.30 mg/L. After matrix-matched standards calibration, recoveries were between 60 and 140%. For the most of pesticides, precision and repeatability were less than 10% and 16%, respectively. The result indicated that the developed method was suitable for the determination of the multi-pesticides in rice wine.展开更多
Based on the theory of human nature and community,this paper analyzes some problems such as the weakening of moral appeal,the loss of moral behavior,the supremacy of physical values and the unclear role orientation fa...Based on the theory of human nature and community,this paper analyzes some problems such as the weakening of moral appeal,the loss of moral behavior,the supremacy of physical values and the unclear role orientation faced by some Chinese college students in the course of their moral life so as to cultivate moral feelings and construct moral values,reshape the ethics of behavior,give full play to the main channel of ideological and political theory courses in colleges and universities,inherit the outstanding Chinese traditional culture as the focal point,and probe into the value demands of college students' harmonious moral life.展开更多
Accurate poverty alleviation is a useful practice conducted by the Communist Party of China to lead the poor people out of poverty and achieve the goal of building a well-off society in an all-round way. The remarkabl...Accurate poverty alleviation is a useful practice conducted by the Communist Party of China to lead the poor people out of poverty and achieve the goal of building a well-off society in an all-round way. The remarkable achievements have been made since its launching. However,the impoverished people and some poverty-stricken workers' mentality as well as the scarcity of people's mind patterns have become the obstacle to accurate poverty alleviation work. This will require the strengthening of ideological leadership,the implementation of " getting rid of poverty",the combination of both hard and soft governance and spiritual poverty,the formation of an overall linkage mechanism,and the lifting of material poverty by spiritual poverty alleviation.展开更多
Four new chlorinated carbazole alkaloids,chlocarbazomycins(CCBs)A-D,were isolated from sponge associated bacterium Streptomyces diacarni LHW51701.Their structures were elucidated via spectroscopic techniques(including...Four new chlorinated carbazole alkaloids,chlocarbazomycins(CCBs)A-D,were isolated from sponge associated bacterium Streptomyces diacarni LHW51701.Their structures were elucidated via spectroscopic techniques(including HRESIMS,ID&2D NMR),and X-ray crystallographic analysis.Structurally,the 4-chloro coupled with 3-methoxyl substituents in the tricycle nucleus of CCBs A-D and the A/-methoxyl group of CCB-D are rare in naturally occurred tricyclic carbazole alkaloids.Moreover,CCBs A-D do not bear the typical Cl poro-alkyl and C2 meto-methyl side chains of bacterial tricycle carbazoles,suggesting a novel mechanism of aromatic ring formation in biosynthesis.The biological evaluation showed that CCB-C possessed inhibitory activities against pathogenic microorganisms including methicillin-resistant Staphylococcus aureus(MRSA),Mycobacterium smegmatis,Bacillus mycoides,and Candida albicans.展开更多
As one of the most environmentally friendly photovoltaic(PV)conversion equipments,aqueousprocessed CdTe nanocrystal solar cells(NC SCs)have attracted great interest in recent years because of their excellent propertie...As one of the most environmentally friendly photovoltaic(PV)conversion equipments,aqueousprocessed CdTe nanocrystal solar cells(NC SCs)have attracted great interest in recent years because of their excellent properties such as high charge-carrier mobility and broad absorption.However,two issues including interfacial recombination and leakage current seriously restrict their performance.In this paper,insulating polymer poly(vinyl pyrrolidone)(PVP)is introduced into CdTe NC SCs to solve the problems.The experimental results of transmission electron microscopy(TEM),atomic force micro scopy(AFM)and dark current measurements,etc.,demonstrate the leakage current is effectively suppressed by introducing PVP.Through further designing device structure,the reduction of interfacial recombination after introducing PVP is confirmed.By strategically taking the advantages of PVP properties(e.g.,water solubility and thermostability),the power conversion efficiency of the devices with PVP is enhanced by almost 37%compared to pure CdTe devices.This work demonstrates an effective and low-cost method to fabricate NC SCs via aqueous route.Moreover,it also proves that appropriate content of insulating polymer is of beneficial in promoting the PV performance.展开更多
文摘A rapid method was developed for the determination of 22 pesticides in rice wine. The procedure involved an extraction with acetonitrile and a cleanup step using dispersive solid-phase extraction (d-SPE), and primary-secondary amine (PSA) and octadecylsilane (ODS) were used as sorbents. D-SPE had some advantages over some traditional prepara- tions, especially in time and cost. Both the extraction and cleanup only cost about 15 min per a sample. Then the GC-MS was used for quantitative and qualitative analysis. Matrix-matched standards solution and analyte protectant were compared to decrease the matrix effect, and the former showed a better efficacy. Acceptable linearity was achieved in the range of 0.05 - 0.30 mg/L. After matrix-matched standards calibration, recoveries were between 60 and 140%. For the most of pesticides, precision and repeatability were less than 10% and 16%, respectively. The result indicated that the developed method was suitable for the determination of the multi-pesticides in rice wine.
文摘Based on the theory of human nature and community,this paper analyzes some problems such as the weakening of moral appeal,the loss of moral behavior,the supremacy of physical values and the unclear role orientation faced by some Chinese college students in the course of their moral life so as to cultivate moral feelings and construct moral values,reshape the ethics of behavior,give full play to the main channel of ideological and political theory courses in colleges and universities,inherit the outstanding Chinese traditional culture as the focal point,and probe into the value demands of college students' harmonious moral life.
文摘Accurate poverty alleviation is a useful practice conducted by the Communist Party of China to lead the poor people out of poverty and achieve the goal of building a well-off society in an all-round way. The remarkable achievements have been made since its launching. However,the impoverished people and some poverty-stricken workers' mentality as well as the scarcity of people's mind patterns have become the obstacle to accurate poverty alleviation work. This will require the strengthening of ideological leadership,the implementation of " getting rid of poverty",the combination of both hard and soft governance and spiritual poverty,the formation of an overall linkage mechanism,and the lifting of material poverty by spiritual poverty alleviation.
基金the National Key R&D Program of China(No.2019YFC0312501)the National Natural Science Foundation of China(No.31929001)+2 种基金the Special Project for Marine Economic Development(Six Major Marine Industries)of Guangdong Province Department of Natural Resources of Guangdong Province(No.[2020]039)the Construction Project of Shanghai Key Laboratory of Molecular Imaging(No.18DZ2260400)the Innovative Research Team of High-Level Local Universities in Shanghai,and the Taishan Scholar Project from Shandong Province to H.L.The authors are grateful to Ying Wu for QTOF mass analysis,Hong-Yan Liu for NMR analysis,and Prof.Meifeng Tao from School of Life Sciences and Biotechnology,Shanghai Jiao Tong University for kindly providing the indicator strains for bioactivity assay.
文摘Four new chlorinated carbazole alkaloids,chlocarbazomycins(CCBs)A-D,were isolated from sponge associated bacterium Streptomyces diacarni LHW51701.Their structures were elucidated via spectroscopic techniques(including HRESIMS,ID&2D NMR),and X-ray crystallographic analysis.Structurally,the 4-chloro coupled with 3-methoxyl substituents in the tricycle nucleus of CCBs A-D and the A/-methoxyl group of CCB-D are rare in naturally occurred tricyclic carbazole alkaloids.Moreover,CCBs A-D do not bear the typical Cl poro-alkyl and C2 meto-methyl side chains of bacterial tricycle carbazoles,suggesting a novel mechanism of aromatic ring formation in biosynthesis.The biological evaluation showed that CCB-C possessed inhibitory activities against pathogenic microorganisms including methicillin-resistant Staphylococcus aureus(MRSA),Mycobacterium smegmatis,Bacillus mycoides,and Candida albicans.
基金financially supported by the National Natural Science Foundation of China(NSFC,Nos.21574018,51433003)the Fundamental Research Funds for the Central Universities(No.2412019ZD002)。
文摘As one of the most environmentally friendly photovoltaic(PV)conversion equipments,aqueousprocessed CdTe nanocrystal solar cells(NC SCs)have attracted great interest in recent years because of their excellent properties such as high charge-carrier mobility and broad absorption.However,two issues including interfacial recombination and leakage current seriously restrict their performance.In this paper,insulating polymer poly(vinyl pyrrolidone)(PVP)is introduced into CdTe NC SCs to solve the problems.The experimental results of transmission electron microscopy(TEM),atomic force micro scopy(AFM)and dark current measurements,etc.,demonstrate the leakage current is effectively suppressed by introducing PVP.Through further designing device structure,the reduction of interfacial recombination after introducing PVP is confirmed.By strategically taking the advantages of PVP properties(e.g.,water solubility and thermostability),the power conversion efficiency of the devices with PVP is enhanced by almost 37%compared to pure CdTe devices.This work demonstrates an effective and low-cost method to fabricate NC SCs via aqueous route.Moreover,it also proves that appropriate content of insulating polymer is of beneficial in promoting the PV performance.
